The top photo is a detail of a long drawing of the Mandurah Estuary and Boundary Island. It’s a low island in the estuary and is uninhabited though there is a jetty that boats can tie up to. Sandspits near the island are a great spot for a variety of birds to rest on.
The lower photo shows the rolled up drawing – it’s about 1.25m long. I used pencil on cartridge paper.